School system leaders are discovering the power of data for promoting school improvement. This guide provides practitioners, parents, and community with insights and tools for cultivating a districtwide culture of data-driven inquiry. Chapter 1 points out that data provide quantifiable proof, taking the emotion and rancor out of the decision-making process. Chapter 2 recommends that districts use multiple assessment and nonassessment measures when assessing student performance. Because methods for data collection vary, superintendents should start by asking what they need to know and what data will help answer their questions. Chapter 3 recommends that teachers, principals, district staff, and the community should be involved in gathering, analyzing, and discussing data; and that crafting a comprehensive strategic communications plan can help superintendents identify key messages, audiences, results, and effective tools. Chapter 4 emphasizes that successful data-driven decision-making requires a shift in the culture of a school district that encourages the use and analysis of data without fear of reprisal. Appendix A contains accountability measures, Appendix B contains advice and techniques for working with the media, Appendix C is a list of resources, and Appendix is a glossary. (RT)